Anode, all-solid-state battery including the same, and method of preparing the all-solid-state battery

Abstract

An anode, an all-solid-state battery including the anode, and a method of preparing the all-solid-state battery. The anode includes a three-dimensional (3D) porous current collector including a plurality of voids having a depth H and a radius R, the voids spaced apart from one another by interval P, and an insulator layer disposed on the interval between the plurality of voids; and an interlayer disposed on the 3D porous current collector. The plurality of voids provide provide space for lithium during charge, and provide lithium during discharge, where such voids are absent of lithium before charging or after complete discharge. The plurality of voids satisfy Expression 1:P≤H≤5⁢0⁢P.Expression⁢1

What is claimed is: 
     
         1 . An anode comprising:
 a three-dimensional (3D) porous current collector including a plurality of voids having a depth H and a radius R and spaced apart from one another by interval P, and an insulator layer disposed on the interval between the plurality of voids; and   an interlayer disposed on the 3D porous current collector,   wherein the plurality of voids provide space for lithium during charge, and provide lithium during discharge, where such voids are absent of lithium before charging or after complete discharge,   an area of the plurality of voids and a portion of the insulating layer are in contact with the interlayer,   at least a portion of the plurality of voids includes the interlayer, and   the depth H and the interval P of the plurality of voids satisfy Expression 1:
   P≤H≤50P.  Expression 1
 
   
     
     
         2 . The anode of  claim 1 , wherein the insulating layer s a insulating layer for lithium and electrons, and
 comprises a material with an energy band gap of 3 eV or more.   
     
     
         3 . The anode of  claim 1 , wherein the insulating layer comprises at least one of SiO 2 , MgO, Al 2 O 3 , CaO, ZrSiO 4 , ZrO 2 , HfO 2 , HfSiO 4 , Y 2 O 3 , La 2 O 3 , Si 3 N 4 , SrO, or Ta 2 O 5 . 
     
     
         4 . The anode of  claim 1 , wherein a thickness of the insulating layer is about 5 nm to about 100 nm. 
     
     
         5 . The anode of  claim 1 , wherein the depth H of the plurality of voids is about 1 μm to about 90 μm. 
     
     
         6 . The anode of  claim 1 , wherein the radius R of the plurality of voids is about 1 μm to about 40 μm. 
     
     
         7 . The anode of  claim 1 , wherein the interval P of the plurality of voids is about 1 μm to about 40 μm. 
     
     
         8 . The anode of  claim 1 , wherein the plurality of voids provide a micropattern in which the voids are consistently spaced apart by interval P, and
 a horizontal cross-section of the micropattern has a circular, oval, triangular, square, rectangular, or hexagonal shape.   
     
     
         9 . The anode of  claim 1 , wherein the 3D porous current collector comprises copper, nickel, aluminum, stainless steel, titanium, iron, cobalt, chromium, or an alloy thereof and, other than a natural oxide layer, there is no additional metal oxide or alloy oxide layer present on a surface of the 3D porous current collector. 
     
     
         10 . The anode of  claim 1 , wherein the 3D porous current collector has a foil, foam, or mesh form. 
     
     
         11 . The anode of  claim 1 , wherein a thickness of the 3D porous current collector is about 5 μm to about 100 μm. 
     
     
         12 . The anode of  claim 1 , wherein the interlayer comprises a mixture, complex, or combination of a carbonaceous material and one of a metal or a metalloid. 
     
     
         13 . The anode of  claim 12 , wherein the carbonaceous material comprises amorphous carbon, and
 the metal or the metalloid comprises indium, silicon, gallium, tin, aluminum, titanium, zirconium, niobium, germanium, antimony, bismuth, gold, platinum, palladium, magnesium, silver, zinc, nickel, iron, cobalt, chromium, cesium, sodium, potassium, calcium, yttrium, tantalum, hafnium, barium, vanadium, strontium, lanthanum, or a combination thereof.   
     
     
         14 . The anode of  claim 1 , wherein a thickness of the interlayer is about 1 μm to about 20 μm. 
     
     
         15 . An all-solid-state battery comprising a cathode, an anode of  claim 1 , and a solid electrolyte disposed between the cathode and the anode. 
     
     
         16 . The all-solid-state battery of  claim 15 , wherein a pressure variation of the all-solid-state secondary battery during charging or discharging at 45° C. at 0.1 C in a voltage range of 2.5 V to 4.25 V is about 0.001 MPa to about 1.5 MPa. 
     
     
         17 . A method of preparing an all-solid-state battery, the method comprising:
 applying an interlayer to a substrate and drying the interlayer to provide an interlayer structure;   forming a cathode/solid electrolyte/interlayer structure by sequentially stacking a cathode, a solid electrolyte, and the interlayer structure, and performing a first pressing process to the stacked structure; and   providing an electroformed three-dimensional (3D) porous current collector including a plurality of voids having a depth H and a radius R, the voids spaced apart from one another by interval P, and an insulator layer disposed on the interval between the plurality of voids,   wherein the depth H and the interval P of the plurality of voids satisfy Expression 1:
   P≤H≤50P;  Expression 1
 
   removing the substrate from the cathode/solid electrolyte/interlayer structure to provide an exposed surface of the interlayer; and   arranging the electroformed current collector with the insulator layer facing the exposed surface of the interlayer; and performing a second pressing process.   
     
     
         18 . The method of  claim 17 , wherein the plurality of voids arranged in a micro-pattern in which the voids are consistently spaced apart by interval P,
 the insulating layer comprises a material with an energy band gap of 3 eV or more, and   a horizontal cross-section of the micropattern has a circular, oval, triangular, square, rectangular, or hexagonal shape.   
     
     
         19 . The method of  claim 17 , wherein the first pressing process and the second pressing process are performed by using an isostatic press, and
 pressure applied during the first pressing process is greater than pressure applied during the second pressing process.   
     
     
         20 . The method of  claim 17 , wherein the 3D porous current collector comprises copper, nickel, aluminum, stainless steel, titanium, iron, cobalt, chromium, or an alloy thereof, and for an exception of a natural oxide layer, there is no additional metal oxide or alloy oxide layer present on a surface of the 3D porous current collector.